1. Field of the Invention
The present invention relates to a tool. and more particularly to a ratchet driving tool.
2. Description of the Prior Art
U.S. Pat. No. 5,573,093 to Lee and U.S. Pat. No. 6,047,802 to Huang disclose two typical ratchet tools having a pair of pawls biased to engage with a gear or an internal gear, in order to control the driving direction of the ratchet tools. These kinds of ratchet tools may not sustain or may not be subjected with a great driving or rotational torque or force.
U.S. Pat. No. 6,000,302 to Chiang discloses a typical tool having a rotational driving head and having a button for indirectly controlling the rotational operation of the driving head via a pawl. The button may not be provided with a spring for biasing against the driving head or against the pawl.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional ratchet tools.
The primary objective of the present invention is to provide a ratchet tool including a ratchet device for resisting a great rotational driving force or a driving torque and including a driving head that may be biased and positioned to the handle with a spring biased mechanism provided in a control button.
In accordance with one aspect of the invention, there is provided a ratchet tool comprising a housing including a chamber formed therein and including an internal gear provided therein, a shank rotatably secured to the housing and received in the chamber of the housing, the shank including a pair of notches formed therein and including a partition formed between the notches thereof, and including a pair of actuating surfaces, the notches of the shank being defined between the partition and the actuating surfaces respectively, a first pawl and a second pawl rotatably received in the notches of the shank respectively and engageable with the actuating surfaces of the shank, for engaging with the internal gear and for controlling a driving direction of the housing relative to the shank, means for biasing the first pawl and the second pawl to engage with the internal gear, and means for selectively disengaging the first pawl and the second pawl from the internal gear. The actuating surfaces of the shank is engaged with the pawls for solidly engaging the pawls with the internal gear.
The housing includes a driving stem and a screw hole, the shank includes a bore and a peripheral shoulder, a fastener is engaged in the bore of the shank and has a head engaged with the shoulder of the shank and threaded with the screw hole of the housing for rotatably securing the shank to the housing.
The shank includes a pair of bulges extended inward of the notches of the shank, the first and the second pawls each includes a cavity formed therein for receiving the bulges of the shank and for rotatably securing the first and the second pawls to the shank.
The partition of the shank includes an aperture formed therein, the biasing means includes a spring engaged in the aperture of the partition and engaged with the first and the second pawls.
The selectively disengaging means includes a control ferrule rotatably engaged on the shank and having two blocks engaged with the pawls respectively for disengaging the first and the second pawls from the internal gear when the control ferrule is rotated relative to the shank. A device is further provided for positioning the control ferrule to the shank at a selected angular position.
The control ferrule includes an annular flanges the shank includes a shoulder engaged with the annular flange of the control ferrule, the ratchet tool further includes a sleeve engaged on the shank and engaged with the annular flange of the control ferrule for positioning the control ferrule to the shank.
A seat includes a peripheral portion having a plurality of depression, the shank has an extension rotatably secured to the seat with a shaft, the shank includes a bore for receiving a ball, and means for actuating the ball to engage with either of the depressions of the seat and to position the shank to the seat at any selected angular position.
The shank includes a hole, the actuating means includes a button slidably received in the hole of the shank and having an opening for receiving the ball and for allowing the ball to be disengaged from the seat, the button includes an actuator extended inward of the opening thereof for engaging with the ball and for forcing the ball to engage with either of the depressions of the seat, and a first biasing means for biasing the actuator of the button to engage with the ball and to force the ball to engage with the seat.
A second biasing device may bias the ball to engage with the seat and includes a spring member secured to the button and engaged with the ball. The button includes a cavity formed therein, the spring member includes a leg engaged into the cavity of the button for securing the spring member to the button.
Further objectives and advantages of the present invention will become apparent from a careful reading of a detailed description provided hereinbelow, with appropriate reference to accompanying drawings.